This study will examine patterns of medical care of elderly cancer patients from a representative cross-section of a large metropolitan area; the multidisciplinary team includes a clinical epidemiologist, and operations researcher, two geriatricians, an oncologist and a biostatistician. This study will determine whether patients receive the full benefits of available cancer treatments, and identify some of the factors which may lead to differences in care. The first 3-month phase will analyze existing community registry data to compare delay in diagnosis and severity for different cancer patient age groups, and to assist in refinement of variables for the medical records phase. The second phase will determine whether diagnostic and management differences are confined to certain tumor sites, to care in specific medical settings, or to patients with serious co-morbid disease. Using a well validated technique for evaluating patterns of care called criteria mapping, and controlling for co-existent disease severity using a new severity scale for co-morbid disease, this study will: . Compare patterns of care in the elderly versus younger people in terms of diagnostic evaluation and treatment; . Compare patterns of care in the elderly versus younger patients in terms of time to definitive diagnosis from the onset of common non-specific symptoms; . Compare the side effects of treatment in the elderly with treatment in the young for similar patients undergoing the same treatments; . Compare compliance or completion of treatments in elderly patients versus younger patients. These four questions will be addressed for three tumor sites--breast, prostrate, and colorectal cancer. Patient populations with widely different socioeconomic characteristics, and which utilize different methods of payment for services, will be studied to answer the question of whether elderly cancer patients are being evaluated and managed differently than younger people, despite equivalencies in overall health status. Products resulting from the study include: 1) the branching logic criteria maps, which are algorithmic instruments that can be used, with accompanying manuals, for assessments of patterns of care for the selected common cancer sites in future studies; and 2) a severity index of co-morbid disease that can be used as a stratification variable for clinical trials or community assessments.